Near the earthquake epicenter, waves heights were were at their highest — this chart maxes out at 240 inches or approximately 8 feet, although the swells in Japan were said to be even higher — and tapered as they traveled across the Pacific and reached South America nearly 24 hours later.

NOAA monitors wave heights by using buoys that are strategically placed across the Pacific rim. The NOAA Tsunami Research Center also released a video showing the path of the wave as it sped across the water. You can view that video here. (via Scientific American)